LinuxPPC-Dev Archive on lore.kernel.org
 help / color / mirror / Atom feed
From: Jon Loeliger <jdl@freescale.com>
To: "linuxppc-dev@ozlabs.org" <linuxppc-dev@ozlabs.org>
Subject: DTC memory reserve question
Date: Mon, 18 Jul 2005 15:25:31 -0500	[thread overview]
Message-ID: <1121718331.2400.24.camel@cashmere.sps.mot.com> (raw)

So, when the Device Tree Compiler lays down a memory
reserve table into an assembly file, it always adds
a reserved region covering the whole DT blob itself.
That is, it does this:

        .balign 8
        .globl  dt_reserve_map
dt_reserve_map:
_dt_reserve_map:
        .long   0, _dt_blob_start
        .long   0, _dt_blob_end - _dt_blob_start
        .llong  0
        .llong  0

Naturally, that yields System.map entries like this:

c0013988 t _dt_blob_start
c0013988 T dt_blob_start
c0013988 t _dt_header
c0013988 T dt_header
c00139b0 t _dt_reserve_map
c00139b0 T dt_reserve_map
c00139d0 t _dt_struct_start
c00139d0 T dt_struct_start
c0013df0 t _dt_strings_start
c0013df0 T dt_strings_start
c0013df0 t _dt_struct_end
c0013df0 T dt_struct_end
c0013f05 t _dt_blob_end
c0013f05 T dt_blob_end

Notice that these are 0xC-gazillion addresses.

And way over here in the Ben H documentation, the memory
reserve map is described as containing physical addresses:

   - off_mem_rsvmap

     This is an offset from the beginning of the header to the start
     of the reserved memory map. This map is a list of pairs of 64
     bits integers. Each pair is a physical address and a size. The
     list is terminated by an entry of size 0. This map provides the
     kernel with a list of physical memory areas that are "reserved"
     and thus not to be used for memory allocations, especially during
     early initialisation.

Uh, so here's my dilemma: I can't just pa() all the addresses
that come in from the memreserve table, can I?  They should
already _be_ physical, right?  We aren't going to be able to
handle a mix of them without a flag or test or something?

jdl

             reply	other threads:[~2005-07-18 20:25 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-07-18 20:25 Jon Loeliger [this message]
2005-07-19  2:08 ` DTC memory reserve question Benjamin Herrenschmidt
2005-07-19 15:29   ` Jon Loeliger

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1121718331.2400.24.camel@cashmere.sps.mot.com \
    --to=jdl@freescale.com \
    --cc=linuxppc-dev@ozlabs.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox